This is the microscopic appearance of neoplasia, or uncontrolled new growth, in the uterine cervix. It is arising in the cervical squamous epithelium. Here, the neoplasm is infiltrating into the underlying cervical stroma. Of course, there can be carcinoma in situ in which a full-fledged neoplasm is present, but has not yet invaded below the basement membrane. Over time, neoplasms may acquire characteristics that make them more able to invade tissues, and this ability to invade distinguishes them as malignant.